EP1776219B1 - Method for producing a molded soundproof part comprising a mass and a springy part - Google Patents

Abstract

The invention relates to a method of producing a sound insulation molding with mass (2) and spring (3), wherein both mass (2) and spring (3) are produced on the basis of the same material, in particular polyurethane. For the formation of a mass, reaction substances and fillers are brought into a mold, in particular sprayed in or injected, and brought to reaction. The spraying in or injection is thereby controlled such that the reaction substances and the fillers are supplied in locally different quantity and/or composition into the mold, dependent upon the sound damping to be locally achieved together with the spring, which is then formed on the so-formed mass (2) in the same mold through formation of foam. Through this, with surfaces to be sound insulated which are of the same geometry, three-dimensional moldings (1) of the same geometry can be produced with both different acoustic and also mechanical behavior in predetermined series.

Description

The invention relates to a method for producing a sound insulation molding with mass and spring.

From the EP 0 882 561 A1 For example, there is known a method for manufacturing a sound-insulating molding with mass and spring, in which both the mass and the spring are manufactured on the basis of the same material, namely polyurethane. In order to form a mass, reactants and fillers are sprayed or injected into a mold and allowed to react, a shaping of the mass being achieved as a mass layer by means of a punch. Subsequently, foam is formed as a spring on the mass in the same shape and that by means of a second molding, through which the mass layer is backfoamed. The features of the preamble of claim 1 are thus known from this document.

In the known procedure, a continuous mass layer is achieved with substantially the same thickness, wherein the visible side can have individual profiles in the form of grooves or ribs by appropriate training in particular the form. The spring, or foam layer, may also be deformed. As a result, the molded part can be adapted to specific courses of a surface to be sound-insulated, to which the molded part is then to be attached.

US 2004/0150128 A1 describes a method for producing a mass layer, in which first a heavy layer of uniform thickness is produced by calendering and subsequently extruded additives are applied to the layer, which join with it.

The cost of materials required in the production of the mass or heavy layer is considerable and therefore costly. In addition, a reasonably economical production is possible only in large quantities. Typical moldings of the type described are used in vehicles, especially passenger cars. Passenger cars are offered with the same body design with very different engines, so that in the design of the molded part and in particular its mass or heavy layer the worst case constellation of an engine as a noise and the sound-insulating surface must be used by the molding.

Proceeding from this, it is an object of the present invention to provide a procedure by means of which high sound insulation or soundproofing effect can be achieved at low cost of materials.

According to the invention, the spraying is controlled according to the characterizing part of claim 1.

The invention is based on the recognition that an area excited by a sound exciter transmits the sound very differently, essentially frequency-dependent but also partly dependent on the location. This in turn implies that, within the scope of manufacturing tolerances, there is an optimum mass-spring combination for every surface area of a surface to be sound-insulated. Thus, the cost of materials for the mass and thus for the molding can be optimized as a whole. It is only necessary to appropriately control the devices which effect the injection or injection of the various materials for mass and spring so that locally the reactants (including blowing agents) and the fillers to form the mass or heavy layer in the locally required amount and composition are supplied. In particular, the filler content can be varied in a simple manner, typically between 0 and 50 percent by volume, the amount of reactants supplied can be varied so that different thicknesses of the mass or heavy layer are achieved, typically 0.5 mm and more (even 10 mm ), and the formulation of the reactants can be typically adapted, for example, for polyurethane materials over the entire range, which is known per se from polyurethane chemistry.

Moreover, it is possible to influence not only the acoustic properties by further measures, but also mechanical properties such as mechanical strength or elasticity. For example, where breakthroughs are to be provided in the finished molded part, the mechanical strength is to be increased, whereas where in the finished molded part sealing edges should be provided to other parts, the elasticity should be higher. In a special way, this can be achieved without impairing the acoustical or acoustic properties in that, while maintaining the same density, locally adjacent regions have different compositions of the reactants used.

It turns out that the control of the materials introducing devices is typically done automatically by computer control, as is basically known in robot controllers. It follows, in turn, that the sequence of the control can be quickly adapted to changing conditions, such as the assignment of another sound generator to a sound-insulating surface. Thus, it is even possible to produce not only small series but also individual moldings individually in the desired number and sequence, as is desirable in the just-in-time production. For geometry-like molded parts, it may be sufficient to provide a single tool, depending on the number of pieces to be manufactured per unit of time. Depending on the size of the molded part, it may even be possible to design a mobile manufacturing device that can be used flexibly on site.

Especially with the use of exclusively PUR materials can be considered due to the ability to customize individual moldings, special requests, for example, in terms of color design.

Fig. 1

in isometrischer Darstellung und im Schnitt den grundsätzlichen Aufbau eines gemäß der Erfindung herstellbaren Formteils,

Fig. 2

schematisch in Aufsicht eine Abwicklung eines Formteils mit Angabe von gemäß der Erfindung zu erreichenden unterschiedlichen Massen bzw. Schwerschichtabschnitten,

Fig. 3

eine perspektivische Ansicht eines kompliziert geformten Karosserieteils als Beispiel einer schallzuisolierenden Fläche mit der Angabe von Flächenabschnitten, in denen bestimmte mechanische Eigenschaften zuzüglich zu akustischen Eigenschaften erhalten werden sollen, wie das durch die Erfindung möglich ist,

Fig. 4

die Anwendung der erfindungsgemäßen Vorgehensweise bei der Ausbildung von Kanten für z. B. Durchbrüche und

Fig. 5

in einer Ansicht ähnlich Fig. 4 die Anwendung der Erfindung bei der Ausbildung elastischer Kanten bzw. Lippen.

The invention will be explained in more detail with reference to the embodiments illustrated in the drawings. Show it:

Fig. 1

in isometric view and in section the basic structure of a producible according to the invention molding,

Fig. 2

schematically a plan view of a development of a molding with specification of according to the invention to be reached different masses or heavy layer sections,

Fig. 3

a perspective view of a complex shaped body part as an example of a sound-insulating surface with the indication of surface portions in which certain mechanical properties plus acoustic properties to be obtained, as is possible by the invention,

Fig. 4

the application of the procedure according to the invention in the formation of edges for z. B. breakthroughs and

Fig. 5

similar in a view Fig. 4 the application of the invention in the Training elastic edges or lips.

Fig. 1 shows a detail section through a molded part 1, consisting of a mass 2 or heavy layer and a spring 3 or foam layer with the same material structure, preferably polyurethane.

Typically, a mass 2 or heavy layer is cell-poor or cell-less and has a high basis weight, which is essentially caused by fillers. The spring 3 or foam layer, however, is rich in cells, has little or no filler content and thus has low basis weight.

Mass 2 and spring 3 cooperate in a conventional manner to achieve a sound attenuation. Furthermore, thickness and density as well as porosity have an influence on the mechanical properties of the molded part 1 at a specific location, as is also known per se.

Fig. 1 schematically illustrates how at a certain, corresponding to the cutout point of the molding 1 on the mass 2 is locally affected. In the exemplary embodiment, the mass 2 consists of second discrete mass layers 4 and 5. The first mass layer 4 can be provided in the same way for the entire molded part 1 throughout and define a supporting layer which influences the essential mechanical properties. Locally, the second discrete mass layer 5 is applied, so that locally the mass 2 is formed by the two layers 4 and 5. The second discrete mass layer 5 may, but need not, have the same composition with respect to the reactants and the amount of filler as the first discrete mass layer 4, and therefore may be made uniform in the same operation. It can also be applied after the formation of the first discrete mass layer 4 in a mold on these in accordance with local conditions. From the foregoing it follows that this local discrete second mass layer 5 can also be formed on the basis of a different composition of the reactants and / or a different amount of filler.

Ultimately, the processes for reacting the reactants taking into account the uptake of the fillers determine whether it is more expedient for a particular point of the molded part 1 to form the mass 2 in the form of several, in the embodiment of two successive layers 4, 5 or in the form of a single layer, the course whose thicknesses and densities are independent of each other. After formation of the mass 2, the spring 3 is produced in a conventional manner by back-foaming.

After a sound-insulating surface usually has a very complicated three-dimensional shape, generating the mass 2, which must be contoured expediently, and according to the invention directly in one of the sound-insulating surface replicated mold half of a mold. The formation of the foam layer of the spring 3 can then take place both in open and in closed form, the latter is useful if the side facing away from the mass 2 of the spring 3 should also be structured or must.

Thus, the molding 1 with mass 2 and spring 3 can be produced in one operation.

It can be seen that the formation of the mass 2 can also take place against a decor part placed in a mold, such as a carpet blank or a material web, but also the formation of the spring 3 between the mass 2 and a decorative part, such as a carpet blank or a material web.

Fig. 2 shows the settlement 6 of a molded part, are marked in the area areas whose occupancy with mass 2 is different. Surface areas 7, 8 and 9 are defined by different tints or hatchings, in which different basis weights (or densities) of the mass 2 and / or different thicknesses of the mass 2 are to be realized. In the development 6, the same hatched or tinted areas are separated from one another by channel-like structures 10. Thus, it is shown that in the application of the mass 2 in the corresponding surface areas of the real shape to form the real molding due to the three-dimensional conditions expediently different application processes are provided, such as by means of other means for supplying the reactants and fillers or by means of a change in setting the spatial position of the means for introducing the reactants and the fillers.

From the above explanation also shows that in much greater variety than by Fig. 2 indicated surface areas can be provided, where the total formed on the molding mass 2 different structure in its conditional by the reactants and Füllstoffmenge composition and its thickness can be achieved.

Fig. 3 shows in perspective view schematically the complicated three-dimensional structure of a sound-insulating surface, as an example an end wall 11 for a typical motor vehicle. An unillustrated molding, which is applied form-fitting manner to this end wall 11 is to have locally different properties, which are represented by different frames and tints. These are combinations of both mechanical properties, which can be represented by words, and acoustic properties, which can be defined by basis masses or basis weights. The details are of course exemplary and real, any desired end wall 11 to be assigned moldings may locally strong deviating both mechanical and acoustic properties. In the example, area regions 12 should have high strength with a basis weight of about 1 kg / m ² , area regions 13 should be soft-elastic with a weight per unit area of 2 kg / m ² , surface areas 14 should be lightweight overall with a basis weight of 1 kg / m ² If surface areas 15 are to have both high strength and be hard and heavy, and also have a basis weight of, for example, 4.5 kg / m ² , surface areas 16 should be heavy with a weight per unit area of approximately 4.5 kg / m ² , should be the remaining surface areas 17 have a basis weight of 2 kg / m ² without predetermined mechanical property and areas 18 are at a basis weight of 1 kg / m ² soft elastic and be formed into an outlet lip. From the above it follows that a mass 2 must be provided with at least a basis weight of 1 kg / m ² throughout, with locally higher basis weights to be provided, and locally additional specific mechnanischen properties are to be achieved.

The mechanical properties are on the one hand by influencing the local composition of the reactant mixtures and the type and proportion of solids possible, but also by acting on the foaming. The latter is possible, for example, in the manner in which this is done EP 1 237 751 A1 the present applicant is explained. However, the mechanical properties can also be influenced in another way.

4 and FIG. 5 On average, they show how their mechanical properties can be influenced by influencing the mass of edges and edges. It should be noted that the acoustic properties are of secondary importance there.

Fig. 4 indicates by analogy Fig. 1 in the case of a molded part 1 consisting of mass 2 and spring 3, a physically pronounced edge 20, in the region of which both first discrete mass layer 4 and second discrete mass layer 5 are made significantly thicker are considered in neighboring areas. In an outer edge region 21 in which, if appropriate, no foam 3 can be provided, for instance to define apertures, comparatively high rigidity is achieved in cooperation with the edge 20.

Fig. 5 also shows a pronounced edge 20 in accordance with Fig. 4 , wherein the two layers 4 and 5 of the mass 2 end within the molding, as shown at 22, such that the foam of the spring 3, as shown at 23, forms an outwardly reaching lip which, when placed against concrete elements, becomes elastic Degree can reach.

Thus, in a mold whose lower mold has a course adapted to a sound-insulating surface, according to the invention individually shaped molded parts can be assigned.

One or more means may be associated with a mold, by means of which the supply of the reactants within the range which is permissible for the production of the product can be set in a selectable manner according to quantity and proportions, fillers also being within the permissible range Range can be added in a selectable manner. For example, a procedure according to DE 101 61 600 A1 Applicant can be applied, which allows the variable and equal entry of fillers in a reagent mixture jet.

The invention is particularly applicable to the production of molded parts for motor vehicles, in particular passenger cars. As is well known, a variety of different drive units are assigned there to an at least partially identical body structure. However, this means that the different drive units as sound exciter sound-insulating surfaces in possibly even extremely different ways stimulate, both in terms of the transmitted frequencies and their respective intensity and in terms of the location of the places maximum sound transmission. The conditions may also change for different types of vehicles (such as cars, convertible, station wagon) for such body parts that are geometrically shaped the same, such as an end wall 11 according to Fig. 3 between the passenger compartment and the engine compartment. On the other hand, experience has shown that the assignment of a body part to a certain drive unit and thus a specific noise exciter (with the same vehicle type) leads to a large extent similar sound transmission conditions in a sound-insulating surface. By The invention can therefore on the one hand in an easy way an optimal acoustic design of a molded part can be achieved taking into account mechanical requirements, on the other hand, a considerable material savings is already possible because the material for the mass can be optimally adapted and the mass has the largest proportion of material ,

Since according to the invention, this optimization for each of the possible assignments of a geometrically equivalent sound-insulating surface to a sound generator, namely a drive unit, taking into account the vehicle type is possible, based on the same shape, which corresponds to the sound-insulating surface constructively, individually and as needed each required molding are optimally manufactured.

Thus, the inventive method is also suitable for the production of small batches and in particular for the provision of geometrically similar moldings of different structure in a predetermined order, as required for example for just-in-time production.

The at least one device for introducing the reactants and fillers in the mold for the production of the mass 2 is suitably controlled automatically in the manner of a robot control, with programs for the automatic control of robots, which serve to coat complicated three-dimensional surfaces, known in principle for coatings are. In addition, however, the locally different mixture of the supplied reactants achieved by the invention to achieve the local mechanical and acoustic properties on the one hand as well as the necessary thickness of the mass to be reached 2 on the other hand must be taken into account in the programming.

For the mentioned typical use of molded parts produced according to the invention, a prototype of the surface to be sound-insulated, together with a prototype of a sound generator, is first of all examined with regard to the sound transmission behavior. It is then determined which areas of the surface to be sound-insulated require special attenuation exceeding a minimum attenuation. Starting from the mechanical specifications and spatial specifications given by the customer with regard to the design of the molded part, in particular on the side facing away from the sound-insulating surface, the ideal construction of a molded part can then be determined. In practice, a classification can be carried out over surface areas, as on the one hand manufacturing tolerances in the production of the sound-insulating surface and the sonic exciter and on the other Working tolerances must be taken into account when controlling the devices for introducing the reactants and fillers or must be accepted. It thus becomes an assignment and classification as they are based Fig. 3 has been explained. Thus, a set of parameters or a parameter matrix can be created, which are specified for a given assignment of a specific sounder to the predetermined sound-insulated surface, the targeted control of the at least one means for introducing the reactants (including propellant) and Fillers allowed.

This examination and evaluation and classification can now be carried out for each assignment of the geometrically equivalent sound-insulating surface to another sound generator. Reliefs may result in the investigation and assessment, if the different sound generators are similar type, as may be the case for example with car engines of different displacement and the same installation position. It may well arise that result in substantially different classifications for several different sound sources taking into account the necessary tolerances mentioned. This would simplify the programming effort.

The various different control programs for controlling the at least one device for introducing the reactants and fillers in the form corresponding to a predetermined sound-insulating surface shape can then be freely selected and used for the production of individual moldings.

Since polyurethane materials in particular are pumpable starting products for the reactants (polyols, isocyanates and blowing agents) and fillers, a system for carrying out the process, ie for producing molded parts according to the invention, can be designed as a mobile unit, provided that the geometry of the Moldings and thus the shape allows.

It should also be noted that it is also possible to incorporate third parts such as additional components before, during or after the formation of the mass 2 in a mold, if required or desired by the customer.

Finally, it should be mentioned that since the same materials are used for both mass and spring, the recyclability is significantly increased.

Claims (10)

1. Method of producing a sound insulation molded part comprising mass and spring, wherein both mass and spring are produced on the basis of the same material, in particular, polyurethane,
   wherein for the formation of the mass (2), reaction substances and fillers are sprayed or injected into a mold and brought to reaction and then foam as a spring (3) is formed on the mass in the same mold,
   characterized in that
   the spraying or injecting of the reaction substances and fillers is controlled such that, for the formation of the mass (2), the reaction substances and the fillers are supplied into the mold in locally required quantity and/or composition, dependent upon the sound damping to be locally achieved by the mass (2) and the spring (3).
2. Method according to claim 1, characterized in that the reaction substances and fillers forming the masses are sprayed in against a decorative part placed previously into the mold, in particular a carpet cutting.
3. Method according to claim 1 or 2, characterized in that the reaction substances and the fillers are sprayed by means of physically separate spraying devices.
4. Method according to claim 1 or 2, characterized in that the reaction substances and the fillers are sprayed by means of a single spraying device which causes intermixing.
5. Method according to any of claims 1 to 4, characterized in that the parameters for the control of the quantity and/or composition of the reaction substances and the fillers are determined on the basis of an analysis of a predetermined surface (11) to be sound insulated and a predetermined sound generator, taking into consideration the spring (3).
6. Method according to claim 5, characterized in that, with a possible association of different predetermined sound generators to a predetermined surface (11) to be sound insulated, corresponding different sets of parameters are determined and, dependent upon a predetermined association of a selected sound generator to the surface (11) to be sound insulated, the respective molded part (1) is produced taking into account the so-determined association.
7. Method according to any of claims 1 to 6, characterized in that spraying is controlled so that, for the formation of the mass (2) the reaction substances and the fillers are further delivered into the mold in locally different quantity and/or composition depending on mechanical properties to be achieved locally.
8. Method according to any of claims 1 to 7, characterized in that forming of the foam of the spring (3) is controlled so that the corresponding reaction substances and, if applicable, fillers are delivered into the mold in locally different composition and/or quantity depending on mechanical properties to be achieved locally.
9. Method according to claim 7 or 8, characterized in that, for the formation of regions of higher stiffness with substantially the same sound engineering effect, the locally different composition of the reaction substances and fillers is controlled so that, for the mass (2) or spring (3), there is achieved substantially the same density as surrounding areas of lower stiffness.
10. Method according to any of claims 1 to 9, characterized in that, before and/or during and/or after formation of the mass (2), additional construction elements are put into the mold at predetermined locations.

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